The invention relates to a unitary wheel system for road vehicles, especially cars, comprising a wheel rim especially manufactured of aluminum, a hub adapter which can be applied to the hub of the vehicle axis or brake disc or brake drum, respectively, by means of screws and further comprising a centric, cylindrical portion extending through the wheel rim and provided with a thread as well as with a centric bore at least open in the direction to the hub of the vehicle axis.
Nowadays the manufacturers of wheels for cars are world-wide forced to manufacture a multiplicity of wheels and to take them in stock, which wheels differ broadly with respect to the rim sizes, especially its diameter and width, in order to satisfy multiple wishes of buyers and to fulfil technical requirements. Thus, the costs for manufacturing and especially those for wheels of aluminum which are increasingly requested because of weight saving reasons, as well as the costs for retaining those wheels in stores are substantial and increase accordingly the price of the car.
A unitary wheel system as generally described above is known from Gertran patent No. 40 23 912. Although that unitary wheel system describes the use of different adapters, one cannot derive from that disclosure that one and the same wheel rim can be fixed to wheel hubs having different diameters of hole circle or wheel hub diameters, respectively. A unitary wheel system according to the general teaching of the subject invention is also known from German utility model No. 90 05 110. According to that known unitary wheel system the wheel rim can be connected by means of a connecting part as well as an exchangeable adapter part the wheel hub.